Visual behaviour of ADHD children during an attention test: An almost forgotten variable

The goal of this study was to examine whether looking away behaviour of ADH D children interferes with their test performance. ADHD and normal children carried out two continuous performance tests (CPTs): one with a regular in terstimulus interval (ISI), and the other with an irregular ISI. Children w ere instructed to push a response button when a target stimulus was present ed on the monitor. The children's visual behaviour was recorded and scored offline. A micro-analysis of the visual behaviour indicated that ADHD child ren timed their looking away behaviour in the regular CPT: i.e. they looked away from the monitor and back in the interval between two succeeding stim uli. As a result they did not miss stimuli. Timing of looking away was less possible in the CPT with the irregular ISI. In this condition, looking awa y interfered with the ADHD children's task accuracy. In sum, looking away b ehaviour had a negative effect on the accuracy of test performance of ADHD children when stimuli were unpredictable. Looking away behaviour was not as sociated with the slower reaction times of the ADHD children. Hence, the of ten reported slowness of ADHD children is not to be explained by their visu al behaviour.